Sub-problem 2d: How Can We Improve the Level of Service at the Ramp Junction at the Northbound On-Ramp to I-87?
Step 2. Results
The tables below show the results of adding a lane to the freeway mainline. The first table shows the input data while the second table shows the output data produced from the HCM analysis.
| Freeway data | AM Peak | PM Peak |
| Number of lanes, N | 4 | |
| Free flow speed, SFF | 55 | |
| Volume | 1,000 | 4,800 |
| Ramp data | AM Peak | PM Peak |
| Ramp volume | 765 | 1,900 |
| Number of lanes on-ramp, N | 1 | |
| Length of acceleration lane, LA | 500 | |
| Output data | AM Peak | PM Peak |
| PFM | 0.24 | 0.08 |
| V12, pc/h | 261 | 415 |
| VFO actual | 1,957 | 7,444 |
| VFO maximum | 9,000 | 9,000 |
| VR12 actual | 1,109 | 2,526 |
| VR12 maximum | 4,600 | 4,600 |
| Density, pc/mi/lane | 10.6 | 21.1 |
| LOS for ramp-freeway junction area of influence | B | C |
| Speed-ramp influence area, mph | 51.3 | 50.8 |
| Speed-outer lanes, mph | 55.0 | 47.5 |
| Speed-all vehicles, mph | 52.8 | 48.6 |
After reviewing the output data shown in the table above, consider the following questions:
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What is the most significant change in the performance of the merge area as a result of the addition of the lane to the freeway mainline?
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Does the addition of the lane produce acceptable performance of the merge area?
Take a few minutes to consider
these questions. When you are ready, continue to the next page.